Experimental SDs (SDautosome) were calculated for each experiment on the basis of the log2 ratios of the 24,392 reliable clones minus the clones removed because of low signal-to-noise ratio (SNR) or high SD of replicate clone measures (SDclone). Thresholds for determining CNV clones were set at a multiple of the SDautosome value. For each experiment, clones were annotated as uninformative if they were filtered via SNR or SDclone, as a CNV loss if the log2 ratio was less than the negative threshold, as unchanged if the log2 ratio was between the negative and positive thresholds, and as a CNV gain if the log2 ratio was above the positive threshold.